Topological Invariant and Quantum Spin Models from MagneticπFluxes in Correlated Topological Insulators

  title={Topological Invariant and Quantum Spin Models from Magnetic$\pi$Fluxes in Correlated Topological Insulators},
  author={Fakher F. Assaad and Martin Bercx and Martin Hohenadler},
  journal={Physical Review X},
The adiabatic insertion of a \pi flux into a quantum spin Hall insulator gives rise to localized spin and charge fluxon states. We demonstrate that \pi fluxes can be used in exact quantum Monte Carlo simulations to identify a correlated Z_2 topological insulator using the example of the Kane-Mele-Hubbard model. In the presence of repulsive interactions, a \pi flux gives rise to a Kramers doublet of spinon states with a Curie law signature in the magnetic susceptibility. Electronic correlations… 
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